1. Field of the Invention
The present invention relates to a fluid power assist system for a motor vehicle. More specifically, this invention relates to a fluid power assist system having a fluid reservoir in cooperation with a pump for a motor vehicle.
2. Prior Art
Conventional vehicles employ power assistance systems in many ways. Power assisted brakes and power assisted steering are just two of such applications. Power assisted steering systems are systems in which the steering force is produced by the driver's muscular energy and by an energy source within the vehicle. For this purpose, a hydraulic oil, which is pressurized by means of a pump and serves to generate or increase the steering power, is provided in a closed system. Power assisted brakes work in a similar manner. The energy source may comprise a vacuum booster for a brake system or a pump driven by flywheel for a steering system. These systems typically include an oil reservoir and the corresponding hoses and pipes which transfer the fluid through the system.
Conventional vehicle power steering systems may mount the oil reservoir on the body structure underneath the hood. In these systems, the power steering oil or fluid is typically collected in the power steering oil reservoir after its use by the steering gear and then supplied to the pump through a large diameter suction hose. The design of this system has its drawbacks. First, the suction hose offers poor under hood appearance. Competition between Original Equipment Manufacturers (OEMs) is fierce in today's marketplace. Under-hood craftsmanship is another area in which OEMs can attempt to differentiate their brand. Second, the suction hose is a costly item. The under-hood hose material is often required to have increased durability and performance requirements. These hoses are often long and must be formed in order to effectively negotiate other components located in the engine compartment. The forming also increases its piece cost. The size of the suction hose requires additional fluid in the system in order to operate the steering system. The assembly costs are increased because of the size of the hoses and overall system, more evacuation and field time is required in the assembly plant. Third, power steering hoses also provide opportunities for leakage which can be a nagging warranty item. Finally, the more fluid required to be pushed through the system requires more energy and adds to fluid consumption. Therefore, what is needed is a power assist system which is better designed for assembly and reduces labor time, eliminates unnecessary parts, reduces warranty, improves under hood appearance, and offers a more efficient and cost saving system.